Original post by RoshniDiyaWe call God Waheguru - Wahe meaning wonderful, wow, awe inspiring. Guru meaning teacher, or one who brings light from the darkness. Waheguru is just a name for God, like Allah. He is not our God but the same God that any monotheistic religion refers to.
Guru Nanak Dev Ji was the first Guru, and the founder of Sikhism. He came into the world in a time of corruption and oppression to show people a different path. All of the 10 Gurus have a divine light within them, and can therefore be seen to be the same person. So the fifth Guru for example, may be referred to as the fifth Nanak.
A very, very short summary of Guru Nanak Dev Ji:
One of the most important beliefs of Sikhism that Guru Nanak Dev Ji set down is that it's necessary to help the needy and the poor. Guru Ji was always ready to help the poor and he served food to them. In fact, Guru Ji often invited the needy and the poor into his house. Another example of Guru Ji helping the poor and the needy occurred while he was a storekeeper. Guru Nanak Dev Ji used to spend a large part of his wages in order to feed the poor and the hungry.
Guru Nanak Dev Ji also taught us that there is one God and he is the Truth and Ultimate Reality. To emphasize this point, Guru Ji said, "There is neither Hindu nor Muslim." In God's eyes, the labels of Hindu, Muslim, Jew, Christian, etc. don't mean anything. Guru Ji also taught that God has created the universe and he is everywhere. In order to spread these messages, Guru Nanak Dev Ji took four long journeys. On these journeys, Guru Ji got many followers and was able to relate his message to many people.
Guru Nanak Dev Ji taught us that all human beings regardless of skin color, wealth, caste, and gender are created equal. When Guru Ji left this world at the age of 70, in 1539, he had laid down the foundations for a great religion.